evaluation of rumble strips on crash reduction

 every year many people are killed on the roads in iran. high rate of crashes, which leave financial damages, injuries, or death consequences, made this topic one of the most controversial issues that any country, especially iran, confronts. a lot of crashes- such as head-on crashes and run-off-the-road (ror) crashes- in fact, results from fatigue or lack of sleep of drivers. this study has represented effectiveness of shoulder and center rumble strips in reducing of accidents on rural roads. their main functions are to alert drivers who are encroaching on the opposing lane or leaving the travel lane by producing vibration and noise when crossed by vehicle tires. according to the result of this survey, shoulder line and center line rumble strips, plays a significant role in decreasing the number of head-on crashes and run-off-the-road (ror) crashes.